Is it a Food Allergy or Acid Reflux?

Think you have a food allergy? Your symptoms could be a sign of something else.

A study conducted by the U.S. government found that previous data on food allergies is significantly inaccurate, including poorly done studies and high percentages of misdiagnoses.

Only about 4 percent of the adult U.S. population has a legitimate food allergy, according to the Mayo Clinic Web site.

But, over 30 percent of Americans believe they have food allergies. This could be because more children are allergic to foods, but grow out of the allergy as they grow older. As adults, they may still assume they have the same food allergies, and avoid foods like nuts, shellfish and eggs, unknowingly for no reason.

Others misinterpret their acid reflux and gastrointestinal (GI) tract symptoms after eating certain foods to be an allergic reaction.

Dr. Anish Sheth, a gastroenterologist and author of “What’s Your Poo Telling You?,” said he agrees that too many people assume they have food allergies, and often sees patients who suffer from a different condition.

“Much more often than not, it is a case of irritable bowel syndrome,” he said. “If they have vague abdominal complaints, one of the most common misconceptions is that their symptoms are a food allergy,” Sheth told FoxNews.com.

In the government commissioned study, more than12,000 papers, studies and other data from 1988 to 2009 were reviewed. Only 72 of those articles met the criteria for a valid study of allergic responses.

One particular condition that can alarm patients into thinking they are having an allergic reaction while eating is eosinophilic esophagitis, or inflammation of the esophagus.

“Eosinophilic esophagitis is becoming increasingly common,” Sheth said. “It can cause symptoms like heartburn that don’t get better with antacid drugs, trouble swallowing, heartburn symptoms that don’t get better with acid blockers and complaints of food getting stuck in the esophagus, which are very similar to symptoms of an allergic reaction. But, with pain, bloating and GI discomfort, the vast majority of patients do not have food allergies.”

Patients unsure of the cause of their symptoms should see their doctor and consider allergy testing.

The study will be published in The Journal of the American Medical Association Wednesday. It is the first step of a large project by the National Institute of Allergy and Infectious Diseases to attempt to set guidelines for food allergy testing.